1. Scope of Invention
This invention relates generally to surgical apparatus and methods for repair of torn tissue, and more particularly to an apparatus and method for arthroscopic and general surgical repair of torn tissue and tissue reattachment by anchoring the tissue against the outer surface of tissue substrate.
2. Prior Art
The rotator cuff is composed of four tendons that blend together to help stabilize and move the shoulder. When a tear occurs in the rotator cuff of the shoulder, it is often necessary to reattach the torn tendon or tendons to the bone of the humeral head.
In a common prior art rotator cuff reattachment technique, the torn cuff is punctured by a punch, and prethreaded suture anchor screws (soft tissue fasteners) are drilled into the head of the humerus bone and the sutures threaded through the anchor screws are passed through the cuff in a difficult procedure using suture relay devices to pass the sutures through the tissue. After the suture strands are passed through the tissue, they are knotted and tied together to secure the reattached rotator cuff to the humerus head. Other types of prior art suture anchors are conically shaped members that are pressed into holes drilled into the bone and engage the cancellous mass surrounding the drilled hole.
A major problem with the above described suture anchoring technique is that the threaded suture anchor screws or conically shaped anchors are threadedly or otherwise secured to the cancellous bone mass beneath the near cortex of the head of the humerus, and depend on this cancellous mass for fixation. It is well known that the cancellous bone mass is susceptible to osteopenic changes (diminished amount of bone tissue).
As a result, the pull-out strength of suture anchors which are depend on the cancellous bone mass beneath the cortex of the bone is subject to becoming diminished with time, and the anchors will tend to loosen, thereby possibly requiring a second operation to remove the loosened suture anchor.
Another problem with the conventional technique is that, in most cases, the sutures are not passed through the tissue when the anchor is set, and thus a difficult procedural step is required using devices such as punches and suture relays to pass and tie the sutures through the torn tissue.
The present invention is distinguished over the prior art in general, by an apparatus and method for arthroscopic repair of torn tissue such as a rotator cuff wherein torn tissue such as a rotator cuff is positioned on the bone exterior by a tissue grasper. A cannula is inserted through the skin substantially to the torn tissue. A drill guide is inserted into the cannula, a drill bit is inserted into the drill guide, and a hole is drilled through the torn tissue and completely through the bone. The drill bit is removed and an inner cannula is passed through the drill guide until its distal end is engaged on the torn tissue or alternatively passed through the hole until its distal end is at the far end of the drilled hole. A soft tissue anchor having expandable wings at its distal end and sutures secured to an eyelet at its proximal end is releasably connected to the distal end of a tubular deployment tool with the free ends of the sutures extending through the deployment tool.
The deployment tool is passed through the inner cannula and drilled hole until the expandable wings clear the far end of the hole a sufficient distance to allow the wings to expand to a diameter larger than the diameter of the drilled hole. The deployment tool, inner cannula, drill guide, and cannula are removed and tension is applied to the suture to engage the expanded wings of the anchor on the exterior surface of the bone surrounding the drilled hole. A button is run down on the sutures through the cannula and secured on the torn tissue by the sutures such that the torn tissue is secured to the bone and the sutures are anchored to the hard exterior surface of the bone by the expanded anchor.
Unlike conventional soft tissues anchors which are anchored in the cancellous bone mass beneath the near cortex of the bone, the present invention in one embodiment provides a suture anchor which is engaged on the exterior of the far cortex of the bone and completely bypasses the cancellous bone mass. The cortex of the bone is much less susceptible to osteopenia than the cancellous interior of the bone.
With the present invention, the sutures are passed through the tissue when the anchor is set, and thus the difficult procedural step and use of devices such as punches and suture relays to pass and tie the sutures through the torn tissue is eliminated.
Calibrated markings on the deployment system of the present invention allow for precise measurement of the far cortex and precise measurement of the depth of insertion and engagement of the anchor device on the far cortex, such that structures beyond the cortex are not violated, and the button hold-down feature eliminates the traditionally difficult arthroscopic tying techniques.
In another broader aspect of the invention, the surgical apparatus includes any form of a tissue substrate anchor of a conventional well-known structure, an elongated suture member securable at its proximal end to the anchor, and a separate torn tissue retainer which lockably engages as desired along the length of the suture member. The suture member extending through the torn tissue from the anchor and the tissue substrate. The torn tissue retainer is movable along the length of the exposed portion of the suture member until it is tightly positioned against the torn tissue and automatically locked in that position by non-reversible lockable engagement with the suture member. A separate tissue gripping member formed preferably as a semi-flexible plate or disc having a substantially larger surface area than the tissue retainer is also provided for enhanced retention of the torn tissue in place against the outer surface of the tissue substrate.
Still another broad aspect of this invention is directed to a surgical apparatus which includes an integrally formed tissue substrate anchor having an elongated suture member formed as a unit therewith. A separate disc-shaped retainer lockingly engages with the exposed distal end of the suture portion at any desired point along the suture interlocking portion. The tissue retainer is therefore moveable along the length of the exposed engaging members of the suture member for tightening the tissue layer against the tissue substrate. Utilized another way, a tear such as that found within a torn meniscus may be reconnected utilizing this embodiment of the invention.
This invention is directed to a surgical apparatus for anchoring and reattachment of torn tissue such as a rotator cuff against on the outer or exterior surface of a tissue substrate such as bone or cartilage. The invention includes a tissue substrate anchor such as that having expandable wings, an elongated suture member securable at its proximal end to the tissue substrate anchor, and a torn tissue retainer lockingly attachable along the length of the suture member by mating interlocking structure therebetween. Tension is applied to the free distal end of the suture member while the tissue retainer is moved longitudinally along the suture member, forcing the tissue retainer to secure the torn tissue against the tissue substrate outer surface. A separate torn tissue gripping member may also be provided for broadened and enhanced torn tissue securement against the tissue substrate.
It is therefore an object of the present invention to provide an apparatus and method for arthroscopic repair of torn tissue such as a rotator cuff which engages a suture anchor on the exterior of the far cortex of the bone and completely bypasses the cancellous bone mass.
It is therefore an object of the present invention to provide an apparatus and method for arthroscopic repair of torn tissue such as a, rotator cuff which passes the sutures through the tissue when the anchor is set, and eliminates the difficult procedural step and use of devices such as punches and suture relays to pass and tie the sutures through the torn tissue.
Another object of this invention is to provide an apparatus and method for arthroscopic repair of torn tissue such as a rotator cuff which utilizes suture anchoring apparatus having calibrated markings for precise measurement of the far cortex and the depth of insertion and engagement of the anchor device on the far cortex, such that structures beyond the cortex are not violated.
A further object of this invention is to provide an apparatus and method for arthroscopic repair of torn tissue such as a rotator cuff that utilizes a button hold-down feature which substantially eliminates traditionally difficult arthroscopic suture tying techniques.
A still further object of this invention is to provide an apparatus for arthroscopic repair of torn tissue such as a rotator cuff which is simple in construction, inexpensive to manufacture, and rugged and reliable in operation.
A yet further object of this invention is to provide a surgical apparatus for reattaching torn tissue in any form atop a tissue substrate of any consistency utilizing a conventional tissue substrate anchor and a unique elongated suture member which is lockingly interengageable to a tissue retaining member which lockably engage one to another after the proximal end of the suture member is attached to the anchor.
In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with reference to the accompanying drawings.
The above noted objects and other objects of the invention are accomplished by the present invention in one embodiment wherein torn tissue such as a rotator cuff is positioned on the bone exterior by a tissue grasper. A cannula is inserted through the skin substantially to the torn tissue. A drill guide is inserted into the cannula, a drill bit is inserted into the drill guide, and a hole is drilled through the torn tissue and completely through the bone. The drill bit is removed and an inner cannula is passed through the drill guide until its distal end is engaged on the torn tissue or alternatively passed through the hole until its distal end is at the far end of the drilled hole.
A soft tissue anchor in one embodiment having expandable wings at its distal end and sutures secured to an eyelet at its proximal end is releasably connected to the distal end of a tubular deployment tool with the free ends of the sutures extending through the deployment tool. The deployment tool is passed through the inner cannula and drilled hole until the expandable wings clear the far end of the hole a sufficient distance to allow the wings to expand to a diameter larger than the diameter of the drilled hole.
The deployment tool, inner cannula, drill guide, and cannula are removed and tension is applied to the suture to engage the expanded wings of the anchor on the exterior surface of the bone surrounding the drilled hole. A button is run down on the sutures through the cannula and secured on the torn tissue by the sutures such that the torn tissue is secured to the bone and the sutures are anchored to the hard exterior surface of the bone by the expanded anchor.
A broader embodiment of the invention provides for the reattachment of any torn or damaged tissue or artificial tissue to any form of tissue substrate by the use of a tissue substrate anchor of any generally well known structure. A primary aspect of the broader invention is the utilization of an elongated suture member attachable at its proximal end to the anchor as or after it is positioned and secured within the tissue substrate. The distal exposed end portion of the suture member extends from the tissue substrate and through the torn or damaged tissue after being normally positioned atop the tissue substrate. Thereafter, a separate tissue retainer is lockably engaged along the exposed length of the suture member and tightened against the torn tissue to retain it in position against the tissue substrate. A separate tissue gripping plate positioned between the torn tissue and the corresponding surface of the tissue retainer may preferably be provided for enhanced torn tissue placement and retention.